Wireless data networks serve wireless User Equipment (UEs) with mobile data communication services like internet access, voice calling, and video calling. The wireless UEs could be computers, phones, headsets, graphic displays, vehicles, drones, or some other wireless communication apparatus. The wireless data networks have wireless access points that exchange user data and signaling over the air with these wireless UEs. The wireless access points include Distributed Unit (DU) circuitry. The DU circuitry uses network protocols like Fifth Generation New Radio (5GNR), Long Term Evolution (LTE), and Institute of Electrical and Electronic Engineers 802.11 (WIFI). The DU circuitry executes network software applications to process the user data responsive to the signaling. The network software applications comprise: Physical Layer (PHY), Media Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (RRC). These network software applications drive the DU circuitry to exchange wireless user data and signaling with the wireless UEs.
The network software applications also drive the DU circuitry to exchange user data and signaling with Central Unit (CU) circuitry. The CU circuitry is located in a data center between the DU circuitry in the wireless access points and the wireless network core. The CU circuitry is often proximate to the DU circuitry, but the CU circuitry may be distant from the DU circuitry. The CU circuitry executes network software applications that drive the CU circuitry to exchange user data and signaling with the DU circuitry in the wireless access points and with the wireless network core.
With the introduction of protocol split technology, some of the network software applications are moved from the DU circuitry in the wireless access points to the CU circuitry in the data center. For example, the RRC and PDCP software applications have been moved from the DU circuitry in the wireless access points to the CU circuitry in the data center. In another example, the MAC, RLC, RRC, and PDCP software applications were moved from the DU circuitry in the wireless access points to the CU circuitry. In yet another example, the DU circuitry in the wireless access points host a lower PHY, and the CU circuitry hosts a higher PHY along with the MAC, RLC, PDCP, and RRC software applications.
In addition to protocol split, Uplink/Downlink (UL/DL) de-coupling technology is used to separate the DU and CU circuitry on the UL and/or the DL. Thus, a wireless UE may get its UL from DU circuitry in an LTE evolved NodeB and get its DL from DU circuitry in an 5GNR NodeB. Likewise, the UL for the wireless UE may traverse CU circuitry in one backhaul link, and the DL for the wireless UE may traverse different CU circuitry in another backhaul link.
Both LTE and WIFI may be used to access the same PDCP component using LTE/WIFI Aggregation (LWA). Both LTE and 5GNR may be used to access the same CU circuitry using a 5GNR Non-Stand Alone (NSA) configuration. Unfortunately, the LTE PDCP component and the 5GNR PDCP component have not been optimized in CU circuitry that also hosts the higher PHYs to effectively and efficiently serve WIFI UEs, LTE UEs, and 5GNR UEs.